Dangote refinery is looking for millions of barrels of U.S. crude oil, according to a document seen by Reuters.

The 650,000-barrel-a-day refinery, which is hoping to emerge at full capacity to become the continent’s largest this year or next, is in the market for two million barrels of West Texas Intermediate (WTI) Midland crude every month for a year starting in July, the tender document shared by two traders showed.

Nigeria, meanwhile, is sitting on a surplus of its own light sweet grades. Nigeria’s May-loading cargoes are just about sold out, traders said, and at least 30 June cargoes on offer.

US benchmark, West Texas Intermediate (WTI) may not necessarily work out cheaper than a Nigerian grade, as the payment will depend on factors like the timing of the sale and the delivery of the oil, two other trade sources told Reuters.

Angola’s July programme is expected any day now, even as a number of June-loading cargoes are still on offer.